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<TITLE>[Chapter 11] StringReader</TITLE>
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<DIV CLASS=refnamediv>
<H1>StringReader</H1>

<H2>Name</H2>

StringReader

</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.432">Synopsis</A></h2>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Class Name:<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>java.io.StringReader</tt>

<p>
<DT CLASS=varlistentry>Superclass:<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>java.io.Reader</tt>

<p>
<DT CLASS=varlistentry>Immediate Subclasses:<br>
<DD>

<P CLASS=para>
None

<p>
<DT CLASS=varlistentry>Interfaces Implemented:<br>
<DD>

<P CLASS=para>
None

<p>
<DT CLASS=varlistentry>Availability:<br>
<DD>

<P CLASS=para>
New as of JDK 1.1</DL>
</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.433">Description</A></h2>

<P CLASS=para>
The <tt CLASS=literal>StringReader</tt> class represents 
a character stream whose data source is a<tt CLASS=literal> String</tt>. 
This class is similar to the <tt CLASS=literal>CharArrayReader</tt> 
class, which uses a <tt CLASS=literal>char</tt> array 
as its data source. 

<P CLASS=para>
<tt CLASS=literal>StringReader</tt> is meant to replace 
the <tt CLASS=literal>StringBufferInputStream</tt> 
class as of JDK 1.1. Unlike <tt CLASS=literal>StringBufferInputStream</tt>, 
<tt CLASS=literal>StringReader</tt> handles Unicode 
characters and supports <tt CLASS=literal>mark()</tt> 
and <tt CLASS=literal>reset()</tt>. 

</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.434">Class Summary</A></h2>

<DIV CLASS=screen>
<P>
<PRE>
public class java.io.StringReader extends java.io.Reader {
  // Constructors
  public StringReader(String s);
  // Instance Methods
  public void close();
  public void mark(int readAheadLimit);
  public boolean markSupported();
  public int read();
  public int read(char[] cbuf, int off, int len);
  public boolean ready();
  public void reset();
  public long skip(long ns);
}
</PRE>
</DIV>

</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.435">Constructors</A></h2>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.453">StringReader</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.603">public StringReader(String s)</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Parameters<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>s</tt><br>
<DD>

<P CLASS=para>
The <tt CLASS=literal>String</tt> 
to use. </DL>
<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This constructor creates a <tt CLASS=literal>StringReader</tt> 
that uses the given <tt CLASS=literal>String</tt> 
as its data source. The data is not copied, so changes made to the <tt CLASS=literal>String</tt> 
affect the data that the <tt CLASS=literal>StringReader</tt> 
returns. </DL>
</DIV>

</DIV>

</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.436">Instance Methods</A></h2>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.454">close</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.604">public void close()</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.close()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method closes the reader by removing the link between this <tt CLASS=literal>StringReader</tt> 
and the <tt CLASS=literal>String</tt> it was created 
with. </DL>
</DIV>

</DIV>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.455">mark</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.605">public void mark(int readAheadLimit) throws IOException</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Parameters<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>readAheadLimit</tt><br>
<DD>

<P CLASS=para>
The maximum number of characters that can be read before the saved position 
becomes invalid. </DL>
<p>
<DT CLASS=varlistentry>Throws<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>IOException</tt><br>
<DD>

<P CLASS=para>
If the stream 
is closed or any other kind of I/O error occurs. </DL>
<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.mark()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method causes the <tt CLASS=literal>StringReader</tt> 
to remember its current position. A subsequent call to <tt CLASS=literal>reset()</tt> 
causes the object to return to that saved position, and thus re-read a 
portion of the string. Because the data for this stream comes from a <tt CLASS=literal>String</tt>, 
there is no limit on reading ahead, so <tt CLASS=literal>readAheadLimit</tt> 
is ignored. </DL>
</DIV>

</DIV>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.456">markSupported</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.606">public boolean markSupported()</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Returns<br>
<DD>

<P CLASS=para>
The <tt CLASS=literal>boolean</tt> value <tt CLASS=literal>true</tt>. 

<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.markSupported()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method returns <tt CLASS=literal>true</tt> to 
indicate that this class supports <tt CLASS=literal>mark()</tt> 
and <tt CLASS=literal>reset()</tt>. </DL>
</DIV>

</DIV>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.457">read</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.607">public int read() throws IOException</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Returns<br>
<DD>

<P CLASS=para>
The next character or <tt CLASS=literal>-1</tt> if the end of the string is encountered. 

<p>
<DT CLASS=varlistentry>Throws<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>IOException</tt><br>
<DD>

<P CLASS=para>
If the stream 
is closed or any other kind of I/O error occurs. </DL>
<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.read()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method returns the next character from the string. The method cannot 
block. </DL>
</DIV>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.608">public int read(char[] cbuf, int off, int len) throws IOException</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Parameters<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>cbuf</tt><br>
<DD>

<P CLASS=para>
An array of characters to be filled from the stream.

<p>
<DT CLASS=varlistentry><tt CLASS=literal>off</tt><br>
<DD>

<P CLASS=para>
An offset into the character array.

<p>
<DT CLASS=varlistentry><tt CLASS=literal>len</tt><br>
<DD>

<P CLASS=para>
The number of characters to read. </DL>
<p>
<DT CLASS=varlistentry>Returns<br>
<DD>

<P CLASS=para>
The actual number of characters read or <tt CLASS=literal>-1</tt> if the end of the string is 
encountered immediately. 

<p>
<DT CLASS=varlistentry>Throws<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>IOException</tt><br>
<DD>

<P CLASS=para>
If the stream 
is closed or any other kind of I/O error occurs. </DL>
<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.read(char[], int, int)</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method copies up to <tt CLASS=literal>len</tt> 
characters from the internal buffer into the given array <tt CLASS=literal>cbuf</tt>, 
starting at index <tt CLASS=literal>off</tt>. </DL>
</DIV>

</DIV>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.458">ready</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.609">public boolean ready() throws IOException</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Returns<br>
<DD>

<P CLASS=para>
A <tt CLASS=literal>boolean</tt> value that indicates 
whether the stream is ready to be read. 

<p>
<DT CLASS=varlistentry>Throws<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>IOException</tt><br>
<DD>

<P CLASS=para>
If the stream 
is closed or any other kind of I/O error occurs. </DL>
<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.ready()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
If there is any data left to be read from the string, this method returns 
<tt CLASS=literal>true</tt>. </DL>
</DIV>

</DIV>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.459">reset</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.610">public void reset() throws IOException</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Throws<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>IOException</tt><br>
<DD>

<P CLASS=para>
If the stream 
is closed or any other kind of I/O error occurs. </DL>
<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.reset()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method resets the position of the <tt CLASS=literal>StringReader</tt> 
to the position that was saved by calling the <tt CLASS=literal>mark()</tt> 
method. If <tt CLASS=literal>mark()</tt> has not been 
called, the <tt CLASS=literal>StringReader</tt> is 
reset to read from the beginning of the string. </DL>
</DIV>

</DIV>

<DIV CLASS=refsect2>
<h3 CLASS=refsect2><A CLASS="TITLE" NAME="ch11-REFSECT2-AUTOID.460">skip</A></h3>

<DIV CLASS=refsect3>
<h4 CLASS=refsect3><A CLASS="TITLE" NAME="ch11-REFSECT3-AUTOID.611">public long skip(long ns) throws IOException</A></h4>

<DL CLASS=variablelist>
<DT CLASS=varlistentry>Parameters<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>ns</tt><br>
<DD>

<P CLASS=para>
The number of bytes to 
skip. </DL>
<p>
<DT CLASS=varlistentry>Returns<br>
<DD>

<P CLASS=para>
The actual number of bytes skipped. 

<p>
<DT CLASS=varlistentry>Throws<br>
<DD>

<P>
<DL CLASS=variablelist>
<DT CLASS=varlistentry><tt CLASS=literal>IOException</tt><br>
<DD>

<P CLASS=para>
If the stream 
is closed or any other kind of I/O error occurs. </DL>
<p>
<DT CLASS=varlistentry>Overrides<br>
<DD>

<P CLASS=para>
<tt CLASS=literal>Reader.skip()</tt> 

<p>
<DT CLASS=varlistentry>Description<br>
<DD>

<P CLASS=para>
This method skips <tt CLASS=literal>ns</tt> characters of input. If you try 
to skip past the end of the string, the stream is positioned at the end 
of the string. </DL>
</DIV>

</DIV>

</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.437">Inherited Methods</A></h2>

<DIV CLASS=informaltable>
<P>
<TABLE CLASS=INFORMALTABLE>
<TR CLASS=row>
<TH ALIGN="LEFT">

<P CLASS=para>
Method</TH>
<TH ALIGN="LEFT">

<P CLASS=para>
Inherited From</TH>
<TH ALIGN="LEFT">

<P CLASS=para>
Method</TH>
<TH ALIGN="LEFT">

<P CLASS=para>
Inherited From</TH>
</TR>
<TR CLASS=row>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>clone()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>equals (Object)</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
</TR>
<TR CLASS=row>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>finalize()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>getClass()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
</TR>
<TR CLASS=row>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>hashCode()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>notify()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
</TR>
<TR CLASS=row>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>notifyAll()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>read(char[])</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Reader</tt></TD>
</TR>
<TR CLASS=row>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>toString()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>wait()</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
</TR>
<TR CLASS=row>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>wait(long)</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>wait(long, int)</tt></TD>
<TD ALIGN="LEFT">

<P CLASS=para>
<tt CLASS=literal>Object</tt></TD>
</TR>
</TABLE>
<P>
</DIV>

</DIV>

<DIV CLASS=refsect1>
<h2 CLASS=refsect1><A CLASS="TITLE" NAME="ch11-REFSECT1-AUTOID.438">See Also</A></h2>

<P CLASS=para>
<tt CLASS=literal>CharArrayReader</tt>, 
<tt CLASS=literal>IOException</tt>, 
<tt CLASS=literal>Reader</tt>, 
<tt CLASS=literal>String</tt>, 
<tt CLASS=literal>StringBufferInputStream</tt> 
</DIV>


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